Macrobenthic infauna collections were made to investigate potential changes in community structure (abundance, biomass, diversity)
in the Chirikov Basin, northern Bering Sea between 1986 and 2002; one of the biomass hot spot region in the Arctic. Two cruises
to the Chirikov Basin were conducted in the years 1986 and 2002 with the R/V/ Alpha Helix. Samples were taken at the same
20 stations during both cruises, 15 of which were included in this study. Infauna was collected at each station with a 0.1m2
van Veen grab. Total abundance ranged from 343-13,373 individuals m-2 in 1986 and from 1093-11,418 individuals m-2 in 2002.
Biomass ranged from 20-515g wet weight m-2 in 1986 and from 62-1694g wet weight m-2 in 2002. Total abundance and biomass in
the Chirikov Basin were dominated by amphipods of the family Ampeliscidae. Other abundant taxa were other Crustacea, Mollusca
and Polychaeta. Overall, a trend (though not statistically significant at all stations) for hi gher abundance and biomass
was observed in 2002 compared to 1986. This thesis is part of a larger study in the Chirikov Basin that focused on ampeliscid
amphipods only (Coyle et al, Deep-Sea Research II, scheduled for December 2007). This study used the WORMS and ITIS databases
for the taxonomic information. Estimates of abundance are not corrected for detectability.
To asses community structure (abundance, biomass, diversity) of the infauna of the Chirikov Basin, northern Bering Sea for
the years 1986 and 2002.

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ATTRIBUTE ACCURACY REPORT: Accuracy of the van Veen grab was not tested. The complete grab sample was washed over 1 mm screen
and all specimens were preserved and later sorted. When hitting the sea floor, van Veen grabs blow away an unknown (specimen-density
specific) portion of the sediment surface. Despinte this, van Veen grabs are the standard tool for sampling macroinfauna (details
in “Methods for the Study of Marine Benthos by N. A. Holme, A. D. McIntyre”)
LOGICAL CONSISTENCY REPORT: The same procedures were used at all sites; findings should be consistent.
COMPLETENESS REPORT: Samples are complete; all taxa were sorted, but not to species level. Ampeliscid amphipods were previously
analyzed by Coyle et al. (see cross reference).
HORIZONTAL POSITIONAL ACCURACY REPORT: Sites were identified using ship GPS (R/V Alpha Helix, out of commission as of 2006)
When not provided by authors, taxonomic information was completed using ITIS and WORMS. Taxon list is based on quantitative
distribution sampling with a van Veen grab and may not represent a complete list of taxa occurring in the region.
PROCESS DESCRIPTION: applicable since fully explained in Methodology: see above. Table of station latitudes and longitudes
are given in Master Thesis.
PROCESS DESCRIPTION: Added AOOS/IOOS core variables. Added ArcOD archive information